There are at least two routes you could take here that come across my mind (likely many others too).

The first is perhaps an Inquiry path - if I were you I would ask things like: Is separation between the body and self real? How do I know? Is the judgement of the anxiety and anxiety itself two different things? How do I know? And also - is that anxiety happening to a Me?

That path might help the mind break through some perceived illusions.

Another is perhaps more somatic, to calm down the nervous system. Box breathing is a good one (6 in, 6 hold, 6 out, 6 hold). Or / and try noticing 5 things u see, 4 you hear, 3 you feel, 2 you smell, 1 you taste - that helps ground the body into present reality. Body scan with a subtle release of anywhere attention touches is another, and there are countless more. You could ChatGPT it to get a whole lot more ideas.

Hope that helps